During long-term use, an electric transformation equipment would have its surface covered with a large quantity of solid particles such as dust, thereby providing the surface of the electric transformation equipment with certain electrical conductivity and thus causing electric leakage during use, which is a waste of resources and brings about some potential safety issues. In order to solve such a problem, an RTV anti-contamination flashover coating material is often coated on the surface of the electric transformation equipment, in which the coating material endows the surface of the electric transformation equipment with strong hydrophobicity to enable the surface to retain hydrophobicity even if it is covered with solid particles. Therefore, the leakage current from the surface is prevented and the flashover voltage is increased.
Hydrophobic agents typically used in RTV anti-contamination flashover coating materials include low-molecular-weight silicone oils (Mw=300-500), dihydroxy(diphenyl)silane, low-molecular-weight fluorine-containing silicone oils, 3# white oil, and the like. These hydrophobic agents are added during the kneading of the coating materials, and are present in the RTV coating layer by means of physical embedding during vulcanization. During use, the hydrophobic agent migrates to the surface by diffusion driven by a concentration difference, has a release rate related to its diffusion coefficient, diffusion area and the like, and is consumed at a high rate. Therefore, increasing the concentration of the hydrophobic agent is a method often used to prolong the service life of an RTV anti-contamination flashover coating material. It is reported, however, that the life of an RTV anti-contamination flashover coating material is nearly not affected by the content of the hydrophobic agent that has been increased above a certain level alone. Therefore, there is a need for other methods of effectively decreasing the release rate of hydrophobic agents.